package com.hmdp.service.impl;

import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;
import com.hmdp.entity.ShopType;
import com.hmdp.mapper.ShopTypeMapper;
import com.hmdp.service.IShopTypeService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisConstants;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.List;
import java.util.concurrent.TimeUnit;

import static com.hmdp.utils.RedisConstants.CACHE_SHOP_TYPE_KEY;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class ShopTypeServiceImpl extends ServiceImpl<ShopTypeMapper, ShopType> implements IShopTypeService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    @Override
    public List<ShopType> queryCache() {
        //先查询缓存
        String key = CACHE_SHOP_TYPE_KEY;
        String shopJson = stringRedisTemplate.opsForValue().get(key);
        if (StrUtil.isNotEmpty(shopJson)) {
            return JSONUtil.toList(shopJson, ShopType.class);
        }
        //为空则查询数据库
        List<ShopType> shopTypes = query().orderByAsc("sort").list();
        if (shopTypes != null) {
            //写入缓存
            stringRedisTemplate.opsForValue().set(key, JSONUtil.toJsonStr(shopTypes), RedisConstants.CACHE_SHOP_TYPE_TTL, TimeUnit.MINUTES);
            return shopTypes;
        }
        return null;
    }
}
